#!/usr/bin/env python3
import argparse
import logging
import socket
import sys

def main():
	parser = argparse.ArgumentParser()
	parser.add_argument("host", help="The IPv6 address of the host to connect to.")
	parser.add_argument("--port", "-p", default=50007, help="The port to connect to.")
	args = parser.parse_args()

	s = None
	for res in socket.getaddrinfo(args.host, args.port, socket.AF_UNSPEC, socket.SOCK_STREAM):
		af, socktype, proto, canonname, sa = res
		try:
			s = socket.socket(af, socktype, proto)
		except OSError as msg:
			s = None
			continue
		try:
			s.connect(sa)
		except OSError as msg:
			s.close()
			s = None
			continue
		break
	if s is None:
		print('could not open socket')
		sys.exit(1)
	print("Entering back-and-forth. You'll get to enter a new message once a message is received. Send SIGINT (use Control-C) to exit")
	with s:
		s.sendall(b'Hello there')
		try:
			while True:
				data = s.recv(1024)
				print(">: ", repr(data))
				response = input("$: ")
				s.sendall(response.encode("UTF-8"))
		except KeyboardInterrupt:
			print("Exiting.")

if __name__ == "__main__":
	main()